Parliament says it has "reached the end of our tether" with prosecutors declining to prosecute illicit cash flow cases.

Parliament has slammed a lack of action by the police and prosecutors on illicit cash outflows, calling for an interministerial committee to be formed to deal with the issue, Business Day reported on Wednesday.

This emerged during a briefing to Parliament's finance committee by the South African Reserve Bank on Tuesday.

Reserve Bank governor Lesetja Kganyago said the Bank had repeatedly laid charges and issued three to four forfeiture orders a month, adding up to about R3 billion a year, for exchange control contraventions, but prosecutors repeatedly declined to prosecute.

The Bank's deputy governor, Kuben Naidoo reportedly said the Bank had handed 41 cases of exchange control contraventions to the police over the last five years, but there had only been one prosecution.

Committee chair, Yunus Carrim reportedly said the committee was "reaching the end of our tether" on the issue.

"We want drastic action. We want to see some of the names in the public domain to appear in court. We are really fed up, to put it mildly," he said.

Carrim reportedly said he had heard that very few of about 5000 cases dealing with illicit financial flows that had been reported to the police of the last few years had been pursued.

A follow-up meeting was scheduled for August 29 where representatives from the Hawks, SAPS, the NPA, SARS, the Financial Intelligence Centre and the Bank will be present.

Meanwhile, Kganyago also warned Parliament that political uncertainty was weighing on the economy, Fin24 reported.

The DA's David Maynier reportedly asked Kganyago about what was going on in the country.

Kganyago reportedly said: "And central bankers are often not worried, so clearly it (political uncertainty) has had an impact...

"Central bankers don't cry wolf unless they're worried. So the uncertainty is impacting on the confidence of investors – and it's no longer just domestic," Kganyago said.